Okay, so in the Lab Assignment that I'm currently working on in AP Biology, there is a question that says:
- What results would you expect if a dialysis bag were filled with glucose and iodine and then placed into a beaker of starch and water?
Its a multiple choice question (which you think would make it easier but in all reality, it just confused me more.
The options were:
*A.)There would be a movement of glucose into the bag, and the water outside of the bag would turn purple.
*B.)There would be movement of glucose out of the bag, and the water outside of the bag would turn purple.
*C.)There would be a movement of starch into the bag, and the inside of the bag would turn purple.
*D.)There would be a movement of starch into the bag and the outside of the bag would turn purple.
First though was that water would move into the bag to an area of lower water potential but then I realized that there is no water in the bag to begin with and it isnt an option. I went over the lab several times and I can't seem to find the answer, the lab didn't come from my textbook so its not in there, and I don't know how to research it on the web because its not a definition or anything - Its lab results. I know that this isn't a place to come for straight answers on homework so I'm not asking for that. Just hoping maybe someone could shine a little light on this and point me in the right direction since at the moment, the information that I have (nothing) is getting me absolutely nowhere. Any help is highly appreciated. Thanks in advance.
I understand your confusion and frustration. Let's break down the question and the options to figure out the correct answer.
From the question, we know that the dialysis bag is filled with glucose and iodine, and it is placed in a beaker of starch and water. Here's what we need to consider:
1. Dialysis bags are selectively permeable, meaning they allow certain molecules to pass through while blocking others based on size and charge.
2. Glucose is a small molecule that can pass through the dialysis membrane, while starch is a large molecule that cannot.
3. Iodine is a small molecule and can diffuse through the dialysis bag since it can pass through the membrane.
Now let's analyze the options:
A.) There would be a movement of glucose into the bag, and the water outside of the bag would turn purple.
This option suggests that glucose would move into the bag, which is correct because glucose is small enough to pass through the dialysis membrane. However, it mentions that the water outside the bag would turn purple, which is incorrect because iodine (which is purple) cannot diffuse out of the bag.
B.) There would be movement of glucose out of the bag, and the water outside of the bag would turn purple.
This option suggests that glucose would move out of the bag. However, since glucose can pass through the dialysis membrane, there would be no reason for it to move out of the bag. Additionally, iodine cannot diffuse through the bag, so the water outside the bag would not turn purple.
C.) There would be a movement of starch into the bag, and the inside of the bag would turn purple.
This option implies that starch would move into the bag, but since starch is a large molecule and cannot pass through the dialysis membrane, this option is incorrect. Additionally, iodine (which is purple) cannot enter the bag.
D.) There would be a movement of starch into the bag, and the outside of the bag would turn purple.
This option suggests that starch would move into the bag, which is incorrect because starch is too large to pass through the dialysis membrane. The outside of the bag turning purple is also incorrect because iodine cannot leave the bag.
Based on our analysis, option A is the most accurate. Glucose, being a small molecule, can move into the bag through the dialysis membrane, while iodine cannot move out. The iodine molecules would stay outside the bag, causing the water outside the bag to turn purple.
Remember, in biology labs, it's essential to consider the properties of molecules, permeability of membranes, and the principles of diffusion when analyzing the movement of substances.